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Diffstat (limited to 'drivers/pci/controller/pci-tegra.c')
-rw-r--r-- | drivers/pci/controller/pci-tegra.c | 11 |
1 files changed, 11 insertions, 0 deletions
diff --git a/drivers/pci/controller/pci-tegra.c b/drivers/pci/controller/pci-tegra.c index cf2398a10d8c..ffe3ad5d0509 100644 --- a/drivers/pci/controller/pci-tegra.c +++ b/drivers/pci/controller/pci-tegra.c @@ -676,6 +676,17 @@ static void tegra_pcie_apply_sw_fixup(struct tegra_pcie_port *port) value |= soc->update_fc_threshold; writel(value, port->base + RP_VEND_XP); } + + /* + * PCIe link doesn't come up with few legacy PCIe endpoints if + * root port advertises both Gen-1 and Gen-2 speeds in Tegra. + * Hence, the strategy followed here is to initially advertise + * only Gen-1 and after link is up, retrain link to Gen-2 speed + */ + value = readl(port->base + RP_LINK_CONTROL_STATUS_2); + value &= ~PCI_EXP_LNKSTA_CLS; + value |= PCI_EXP_LNKSTA_CLS_2_5GB; + writel(value, port->base + RP_LINK_CONTROL_STATUS_2); } static void tegra_pcie_port_enable(struct tegra_pcie_port *port) |